According to a new study by researchers at the University of Otaga in New Zealand, the habits of thumb-sucking and nail-biting may actually be beneficial to your health.
Statistics show that about 50 percent of children suck their thumbs, and 30 percent bite their nails, reports the Daily Mail.
The study, which was published in the journal Pediatrics, was based on the records of 1,037 women and men who have been followed since they were children in the early 1990s as part of a public health study in New Zealand.
All had undergone blood tests to determine if they had any allergies at the age 13 and again at 32. According to Professor Bob Hancox, the study found that an average of 49 percent had at least one allergy at the age of 13 or 32, but that statistic fell to 38 percent if they had bitten their nails or sucked their thumbs as children. If they did both, the risk of having an allergy declined to just 31 percent.
Hancox noted that the findings support the “hygiene hypothesis,” which contends that exposure to microbes reduces your risk of developing allergies.
Stephanie Lynch, a medical student who was also involved in the study, elaborated on the hypothesis.
“They ingest the bacteria living under their nails and as it goes through it may influence the immune system into working in a different way," she said. "That builds an immune response, making them less susceptible to allergies.”
This “hygiene hypothesis” was also articulated by the famed comedian George Carlin in his 1999 television special “You Are All Diseased.” In his standup routine during that show, he said: “What do you think you have an immune system for? It’s for killing germs! But it needs practice. It needs germs to practice on.”
That’s why, he went on to say, “If I drop food on the floor, I pick it up and eat it!”
However, Lynch added a word of caution, the Daily Mail reports.
“I wouldn’t tell children to go out and suck their thumbs but it may just give a little peace of mind to parents and take the stress out," she said.